Pilot trucks for freight services typically comprise signs for warning the oncoming traffic of an oversize load trailing a pilot truck. Some of the existing signs comprise simple banners, but these banners are difficult to see in the dark or in inclement weather. Other existing signs comprise digital signs (i.e., with illumination means). Conventional digital signs for pilot trucks are generally visible from approximately 45 meters away, although the visibility can be greatly increased when the brightness setting of these digital signs is at its maximum setting. However, the brightness of the sign can cause glare or distraction, which can be dangerously blinding to the drivers of the oncoming traffic and cause traffic accidents. In this regard, the invention described herein addresses this problem.